1. Field of the Invention
The invention is related to the field of the determination and optimization of processing stages during the manufacturing of sheet metal forming parts, for example, by means of deep-drawing/stretch-forming processes. It is related to a method, a data processing system, a computer program and a data carrier for the determination of process operations for the description of forming processes on a forming part.
2. Description of Related Art
Sheet metal forming parts, as a rule, are manufactured by deep-drawing. The semi-finished parts, the so-called sheet metal billets (blanks), for this purpose are placed in multi-part forming tools. By means of presses, in which the forming tools are mounted, the parts are formed. The parts, as a rule, are manufactured out of a flat sheet metal billet in several forming stages by means of processing stages such as drawing, restriking, adjusting, etc., in combination with cutting stages.
The dimensioning and adjusting of the forming tools represents a big problem today. Not infrequently several months pass, until a tool works satisfactorily. Frequently it is an iterative process, which is associated with a lot of rejected parts and consumption of energy and resources. The planning today to a great extent takes place manually and exceedingly time-consumingly by means of Computer-Aided-Design systems (CAD). CAD systems of this kind model a geometry of physical bodies, thus in particular of forming parts in different stages of the processing, and of corresponding tools. Understood by “geometry” here is a (computer readable) representation of the geometrical dimensions of a body, for example, in the form of a finite elements grid, or from a quantity of parameterized elemental bodies and/or surfaces.
In this manner, a process layout (method plan) is developed, which among others describes a sequence of part geometries to be produced. In doing so, the model of every state is essentially produced manually out of basic modules or out of another model through the modification of it. The process layout (method plan) as a rule also describes an allocation of individual forming operations to the part geometries. From this, manually, and only to a limited part computer-assisted, are parameters of the forming operations defined and the forming presses, respectively, tools designed.
A process layout (method plan) today as a rule consists of a set of 2D drawings. Starting out from the finished component, first the drawing stage is determined. Starting out from this drawing stage, thereupon the following operations are defined, wherein the restriking, folding, cutting and slider operations are only defined by the indication of the area and the working direction. As a rule, no 3D surfaces are built-up for the tools.
The procedure described is very elaborate and inflexible.